"Deep Color" Gives HDMI a Boost
The High Definition Multimedia Interface specification is the most popular for today's digital television. It has been indispensable in consumer electronics because of its ability to pass high definition content-protected video, as well as audio, from one convenient plug. The group in control of the specification is comprised of Hitachi, Matsushita Electric (Panasonic), Royal Philips Electronics, Silicon Image, Sony Corporation, Thomson and Toshiba Corporation, and is known as the HDMI Licensing LLC. The HDMI LLC has just outlined an upgraded specification that allows HDMI to support "deep color"; the new spec is called HDMI 1.3.
The new HDMI specification will increase the bandwidth to allow support for video at 1080P / 60Hz with 36 bit RGB color. The main reason for the upgrade is to support 30 to 36 and 48 bit RGB also known as "deep color", which takes display devices into color count territory that exceeds the human eye's ability. Most displays today support up to 24 bit color depth or 24 bit RGB, which is equal to 16 million colors. This meets the limits of perception of the human eye - we just can't see any more color than that. However there is degradation in scaling and other effects that you can see. HDMI 1.3 and deep color want to take the color range of displays beyond human perception, so visual problems can't even be seen with the human eye. The new HDMI 1.3 will also support Dolby HD and DTS-HD audio formats, combined with a lip sync compensation feature that synchs audio and video channels.
The option of deep color in consumer electronics gives hardware and media developers a whole new upgrade path. Sony's upcoming PlayStation3 will support deep color. Many PC graphics cards by ATI and Nvidia will add the new specification into upcoming video cards. And of course HD DVD and Blu-ray will have the ability to support deep color, and are really the practical reason for the upgraded HDMI.
A company called eCinema Systems have already developed an LCD display that uses the HDMI 1.3 spec and it should be launched sometime in late '06. By supporting "deep color" in an LCD display, it will overcome LCD's most classic shortcoming in comparison to CRT - that's its inability to show deep, dark black. This new display by eCinema Systems will be able to display 48 bit colors, beyond the scope of human ability to differentiate between colors. The upcoming DMC40HDR 40 inch LCD will boast the darkest black level outputs of any LCD before it. Prior to this advance in LCD, using deep color professional image quality evaluation has always been performed on a CRT.